Like any other car except that you check DAMAGED in the CONDITION box on that site where you are going to put your ad. And later in the description you elaborate on details about the damage. Simple.
I'd go to your local car mechanic, get a quote to repair, then also ask him if he know someone who could buy or or if he can buy it. Car mechanics are probably the fastest route here. They can fix the car at their own expense and sell it for a higher price.
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